Hid usages – MagTek P-SERIES USB User Manual

Page 38

Advertising
background image

P-Series USB Insertion Reader

30

HID USAGES

HID devices send data in reports. Elements of data in a report are identified by unique identifiers
called usages. The structure of the device’s reports and the device’s capabilities are reported to
the host in a report descriptor. The host usually gets the report descriptor only once, right after
the device is plugged in. The report descriptor usages identify the devices capabilities and report
structures. For example, a device could be identified as a keyboard by analyzing the device’s
report descriptor. Usages are four byte integers. The most significant two bytes are called the
usage page and the least significant two bytes are called usage IDs. Usages that are related can
share a common usage page. Usages can be standardized or they can be vendor defined.
Standardized usages such as usages for mice and keyboards can be found in the HID Usage
Tables document and can be downloaded free at

www.usb.org

. Vendor defined usages must

have a usage page in the range 0xff00 – 0xffff. All usages for this device use the standard HID
keyboard usages or vendor defined magnetic stripe reader usage page 0xff00. The vendor
defined usage IDs for this device are defined in the following table. The usage types are also
listed. These usage types are defined in the HID Usage Tables document.

Magnetic Stripe Reader usage page 0xff00:

Usage ID

(Hex)

Usage Name

Usage

Type

Report

Type

20

Command message

Data

Feature

Advertising